The invention relates to a system and a process for the voice input of a destination into a destination guiding system using a defined input dialog into a destination guiding system.
A system and a process of this type are known, for example, from German Patent document DE 197 09 518 C1. In this known process, several operating functions selectable by voice commands are offered to the user. For each selectable operating function, a lexicon is generated from a general databank, whereby a faster and user-friendlier voice-controlled search for destination addresses is to be permitted. In this case, German Patent document DE 197 09 518 C1 is based on known systems, which require a spelling of the destinations. However, a destination guiding system according to German Patent document DE 197 09 518 C1 also does not provide a user-friendly input possibility because, before a destination input, a voice command is first required for the selection of a desired operating function. Before a destination input, the user has to select the manner by which the destination is input; for example, whether the destination is to be spelled, whether the destination is to be searched by way of a destination area input or whether it is to be searched by way of an input of the destination name. The input of the destination name, for example, requires the search in a lexicon with all destination names. In Germany, such a lexicon would comprise a volume of approximately 60,000 locations. This abundance of stored voice statements can no longer be satisfactorily handled by the known voice recognition systems (usually so-called HMM systems) whose limit for a good speed recognition rate is empirically at approximately 1,000 words.
It is an object of the invention to improve a system and a process of the initially mentioned type with respect to an easier operability and with respect to the above-mentioned limit of known voice recognition systems.
This object is achieved by a system for the voice input of a destination by means of a defined input dialog into a destination guiding system in real-time operation. The system has devices, by which an entered voice statement of a user is detected via a voice recognition device. The entered voice statement is compared with stored voice statements and is classified according to its recognition probability by means of which the stored voice statement is recognized as the entered voice statement with the highest recognition probability. The stored voice statements assigned to a destination are composed at least of the destination name and at least a regionally limiting additional information unambiguously identifying the destination name, each destination name being stored with a flag symbol in a first database and each additional information being stored in a second database. Advantageous further developments of the invention are the objects of the dependent claims.
According to the invention, the stored voice statements assigned to a destination are composed at least of the destination name and at least one regionally limiting additional information, which unambiguously identifies the destination name. Each destination name is stored in a first database and each eligible additional information (without any destination name) is stored in a second database. Each piece of data relating to the destination or each input concerning a destination name in the first database comprises a flag symbol. Such a flag symbol may, for example, be a program-related marker for rapidly finding the piece of data. The marker or the flag symbol preferably characterizes the additional information itself assigned to the respective piece of data.
In this case, the second database is naturally much smaller than the first. Regionally limiting additional information consists, for example, of federal states, regional names, administrative districts, rivers, lakes and/or prominent larger cities. The additional information can preferably be differentiated unambiguously; that is, identical additional information does not exist in the second database. This additional information should be so-called identifiers by which the problem of the ambiguity of identical destination names (such as Münster near Straubing, Münster in Lower Franconia) is also solved. The identifiers are preferably selected such that their number does not exceed the above-mentioned limit for good voice recognition.
This databank structure according to the invention is preferably used such that, after an entered voice statement, the latter is in each case first compared with the identifiers stored in the smaller second database. Only when an identifier is recognized in the second database, will the voice recognition of the destination name be continued. In this case, the entire first database is not searched for the destination name with respect to the entered voice statement but only a partial data stock assigned to the recognized identifier and generated from the first database.
In a third database, prepositions can be stored which are used for separating the destination name and the additional information in an entered voice statement.
At best, the user speaks a phrase as a voice statement which consists of the destination name, a preposition and the additional information. However, it is important to the invention that, at the beginning, the input dialog permits a single word input as well as a phrase input, for example, in the form of the destination name, the preposition and the identifier, or in the form of the destination name and the identifier, as the voice input. After the input of a voice statement, the voice recognition device checks whether at least a part of the voice statement is additional information. The voice recognition devices guide the user, as required, that is, particularly when no part of the voice statement is recognized as additional information, in the further course to the voice input of additional information or to a defined phrase input, by which the voice recognition device can recognize that at least a part of the voice statement is additional information.
The user is flexible in the presentation of his voice statement and does not have to make any manual operating function selection (such as a “a destination area input”). In addition, a learning effect takes place. After repeated use, the user will automatically offer to the system the optimal phrase input in the form of the destination name, the preposition and the additional information.
The entered voice statement is preferably assigned by the voice recognition device to one of at least two input categories. In this case, a first input category is defined as a phrase input when the voice recognition device considers a part of the voice statement to be additional information. A second input category is defined as a single word input when the voice recognition device considers no part of the voice statement to be additional information.
When a part of the voice statement is recognized as additional information, then for the voice recognition of the destination name, the entire database will not be searched with respect to the destination name in view of the entered voice statement. On the contrary, by means of the flag symbols from the first database, a partial data stock is generated which is assigned to the known identifier. The partial data stock can be generated on the basis of an environment list assigned to the identifier. Such an environment list contains all destination names or flag symbols of the destination names which are eligible for the respective identifier. The environment lists can be stored inside or outside of the second database. As an alternative, without the presence of such environment lists, the first database can be searched for the flag symbols characterizing the respectively recognized identifier. Finally, the partial data stock contains at least the data of the destination names required for the voice recognition which are eligible with respect to the identifier. Such destination name data comprise particularly also reference models or principles for establishing reference models for the voice recognition according to processes known from the prior art. Therefore, the entered voice statement, for finding the desired destination name, only has to be compared with the respective dynamically generated partial data stock.
If no destination name was recognized, either an input dialog with a repeated query of the destination name or of the additional information can follow, or a list can be offered for the selection of a destination name (for example, by a reading-out and a voice-controlled operation, by a display on the video screen with a manual selection possibility, or by a display on the video screen and a voice-controlled selection).
When no part of the voice statement is considered to be additional information, a search takes place in the second database for the entire voice statement. The purpose of this approach is a fast search for a destination name which may also be an identical additional information. Preferably, only that additional information in the second database is compared with the entered voice statement which may also represent destination names.
When no additional information is recognized in the second database, the user is requested within the scope of another input dialog to carry out a voice input of an additional information. In this case, either an additional information alone or a phrase input (with additional information) may be requested. The previously entered voice statement is preferably interpreted as the destination name and is stored for the later voice recognition of the destination name.
An entered voice statement is categorized as a phrase input when a part of the voice statement is recognized as a preposition or as an identifier which is preceded by a part of the voice statement.
It is an important aspect of the invention that, independently of the form of the voice input, a first search never takes place in the first database but only in the second database. The first database is used as a basis for dynamically generating a partial data stock as a function of the additional information recognized in the second database. The entire first database is never used for the voice recognition of a destination name itself, but only the partial data stock taken from the first database. If no additional information is considered as being recognized, the input dialog of the voice recognition system guides the user at least to an input of the identifier or to the input of a phrase which, according to the definition, contains an identifier.
The drawing illustrates an embodiment of the invention.